As Robert Wagner discovered in 1981 when his wife, Natalie Wood, died, pushing back to work is a painful but necessary step. Now the shattered family on his troubled ABC series, Lime Street, has been forced to share that same understanding. For the first time since its star Samantha Smith died at 13 with her father, Arthur, in a Maine plane crash 10 weeks ago, the entire cast and crew have assembled to resume filming. This is the series' fifth episode, filmed partly in London and half completed when Samantha died.

Maia Brewton, the spunky 8 year old who plays Wagner's other daughter, Margaret Ann Culver, stands in the kitchen on the Lime Street set and calls to her sister washing her hair behind the closed bathroom door—or so the script indicates. "Elizabeth! Elizabeth!" she squeals as the cameras roll. But this time Samantha will not reply. Even hard-boiled crew members are visibly moved.

Putting Maia through a scene bound to cause her pain was not an act of cruelty on the part of Wagner and the producers, but a way to preserve Sam's last performance (the episode will be aired at a later date). Before filming, Wagner had confronted Sam's death openly with Maia. "I talked about missing Sam and how we have to go on," he says. On future shows Elizabeth's disappearance will be ignored. "Why explain something the world already knows?" says Wagner. "I don't believe you can replace a person." The plans now are to audition actresses for the role of an older sister, who will be added to the show.

Since Sam's death Lime Street has faced another serious setback: low Nielsens brought on by an unenviable Saturday night time slot opposite NBC's smash Golden Girls. As a result the one-hour weekly series has been yanked at the producers' request from the ABC schedule until January. When it resumes it will be in a more favorable time slot on a different day.

Sam's death left Wagner once again with the task of explaining a tragedy to his daughters, Natasha, 15, and Courtney, 11. The girls and Sam had struck up an "instant friendship," he says. "When kids are that young and they lose someone who is a contemporary, they have no way of understanding." Courtney asked her father for answers to painful questions. "She was concerned about how Sam was when they found her," says Wagner. "She wanted to know, 'Was she together? Was she in her seat? Where was she in the airplane? Was she cold?' Jane [Samantha's mother] told me later that Arthur must have grabbed Sam and held her because she was pretty much together." In the wreckage authorities found the gold bracelet that Wagner had given Sam in London, inscribed simply, "To Samantha, With Love, RJ."

As Lime Street struggles onward, so does Jane Smith, 40, some 2,600 miles away from Burbank in her Manchester, Maine home. "When I think of what will never be, I get weepy, but I'm trying to look at the future in a positive way," she says. Her mother-in-law now shares her six-room home. Work has proved to be Jane's antidote to pain. Three weeks after the deaths of her husband and only child, she returned to her job as an administrator with the Maine Department of Human Services. She is also setting up the Samantha Smith Foundation, which will start by funding a children's exchange program. Wagner will sit on the board of directors. Smith had the remains of her husband and daughter cremated but is unsure what she'll do with the ashes. "I don't want people traipsing through the house looking for them," she says.

Whether Lime Street ends up a hit or miss, everybody on the set clings to private memories of Samantha. Most remember her gusto. "The first time I had lunch with her, I was expecting these worldly pronouncements," says co-producer Linda Bloodworth. "She kept telling me about her boyfriend and asking if it was okay to cut her hair. It dawned on me that she was just a little girl." But she was also the 11 year old whose 1983 peace plea to Yuri Andropov touched the world with its simplicity. Moved by her spirit (particularly apt now as President Reagan prepares for his summit meeting on Nov. 19-20), Paul Newman and Joanne Woodward are planning a future benefit for the Samantha Smith Foundation.

Bloodworth has announced that all future episodes of Lime Street will be dedicated in the final credits to Samantha. "If we do a hundred episodes that dedication will be seen for 20 years all over the world," says Bloodworth. "That is our goal."